Method and system for monitoring an optical network

Abstract

A method for monitoring an optical network includes communicating optical traffic along a working path of an optical network. The optical network comprises a protection path for the optical traffic to communicate the optical traffic upon a failure in the working path. The protection path comprises two or more network elements coupled together by optical lines. The method also includes monitoring an idle signal of the protection path to detect an error in the protection path comprising an error in a component of one or more of the network elements.

1. A method for monitoring an optical network, comprising:
 communicating optical traffic along a working path of an optical network; 
 the optical network comprising a protection path for the optical traffic to communicate the optical traffic upon a failure in the working path; 
 the protection path comprising two or more network elements coupled together by optical lines; and 
 while communicating optical traffic along the working path, monitoring an idle signal of the protection path to detect an error in the protection path comprising an error in a component of one or more of the network elements. 
 
   
   
     2. The method of  claim 1 , further comprising generating an alarm upon detection of an error in the protection path. 
   
   
     3. The method of  claim 1 , wherein:
 each of the two or more network elements comprises a switch fabric unit along the protection path; 
 the protection path comprises one or more spans interconnecting switch fabric units of adjacent network elements of the two or more network elements; 
 the one or more spans comprising:
 an optical line between the adjacent network elements; 
 interface units between the interconnected switch fabric units; 
 backplanes coupling together components between the interconnected switch fabric units within the adjacent network elements; and 
 the switch fabric units of the adjacent network elements; and 
 
 monitoring an idle signal of the protection path to detect an error in the protection path comprises monitoring each of the one or more spans of the protection path. 
 
   
   
     4. The method of  claim 1 , wherein monitoring an idle signal of the protection path to detect an error in the protection path comprising an error in a component of one or more of the network elements comprises monitoring an idle signal of the protection path to detect an error in the protection path comprising an error in a backplane of one or more of the network elements. 
   
   
     5. The method of  claim 1 , wherein monitoring an idle signal of the protection path to detect an error in the protection path comprising an error in a component of one or more of the network elements comprises monitoring an idle signal of the protection path to detect an error in the protection path comprising an error in an interface unit of one or more of the network elements. 
   
   
     6. The method of  claim 1 , wherein monitoring an idle signal of the protection path to detect an error in the protection path comprising an error in a component of one or more of the network elements comprises monitoring an idle signal of the protection path to detect an error in the protection path comprising an error in a switch fabric unit of one or more of the network elements. 
   
   
     7. The method of  claim 1 , wherein monitoring an idle signal to detect an error comprises monitoring a B3 byte of the idle signal to detect a bit error rate error. 
   
   
     8. The method of  claim 1 , wherein monitoring an idle signal to detect an error comprises monitoring H1 and H2 bytes of the idle signal to detect a loss of pointer-path error. 
   
   
     9. The method of  claim 1 , wherein monitoring an idle signal to detect an error comprises monitoring H1 and H2 bytes of the idle signal to detect an alarm indication signal-path error. 
   
   
     10. A system for monitoring an optical network, comprising:
 an optical network comprising a plurality of network elements coupled together by optical lines; 
 the optical network operable to communicate optical traffic along a working path of the optical network; 
 the optical network comprising a protection path for the optical traffic to communicate the optical traffic upon a failure in the working path; 
 the protection path comprising two or more of the plurality of network elements and the optical lines coupling together the two or more of the plurality of the network elements; and 
 an error detection unit associated with the optical network, the error detection unit operable, while optical traffic is being communicated along the working path, to monitor an idle signal of the protection path to detect an error in the protection path comprising an error in a component of the two or more of the plurality of network elements. 
 
   
   
     11. The system of  claim 10 , wherein the error detection unit is further operable to generate an alarm upon detection of an error in the protection path. 
   
   
     12. The system of  claim 10 , wherein:
 each of the two or more of the plurality of network elements comprises a switch fabric unit along the protection path; 
 the protection path comprises one or more spans interconnecting switch fabric units of adjacent network elements of the two or more of the plurality of network elements; 
 the one or more spans comprising:
 an optical line between the adjacent network elements; 
 interface units between the interconnected switch fabric units; 
 backplanes coupling together components between the interconnected switch fabric units within the adjacent network elements; and 
 the switch fabric units of the adjacent network elements; and 
 
 the error detection unit operable to monitor an idle signal of the protection path to detect an error in the protection path comprises the error detection unit operable to monitor each of the one or more spans of the protection path. 
 
   
   
     13. The system of  claim 10 , wherein the error detection unit operable to monitor an idle signal of the protection path to detect an error in the protection path comprising an error in a component of the two or more of the plurality of network elements comprises the error detection unit operable to monitor an idle signal of the protection path to detect an error in the protection path comprising an error in a backplane of the two or more of the plurality of network elements. 
   
   
     14. The system of  claim 10 , wherein the error detection unit operable to monitor an idle signal of the protection path to detect an error in the protection path comprising an error in a component of the two or more of the plurality of network elements comprises the error detection unit operable to monitor an idle signal of the protection path to detect an error in the protection path comprising an error in an interface unit of the two or more of the plurality of network elements. 
   
   
     15. The system of  claim 10 , wherein the error detection unit operable to monitor an idle signal of the protection path to detect an error in the protection path comprising an error in a component of the two or more of the plurality of network elements comprises the error detection unit operable to monitor an idle signal of the protection path to detect an error in the protection path comprising an error in a switch fabric unit of the two or more of the plurality of network elements. 
   
   
     16. The system of  claim 10 , wherein the error detection unit operable to monitor an idle signal to detect an error comprises the error detection unit operable to monitor a B3 byte of the idle signal to detect a bit error rate error. 
   
   
     17. The system of  claim 10 , wherein the error detection unit operable to monitor an idle signal to detect an error comprises the error detection unit operable to monitor H1 and H2 bytes of the idle signal to detect a loss of pointer-path error. 
   
   
     18. The system of  claim 10 , wherein the error detection unit operable to monitor an idle signal to detect an error comprises the error detection unit operable to monitor H1 and H2 bytes of the idle signal to detect an alarm indication signal-path error. 
   
   
     19. Logic for monitoring an optical network, the logic encoded in a computer-readable medium and operable when executed to perform the steps of:
 communicating optical traffic along a working path of an optical network; 
 the optical network comprising a protection path for the optical traffic to communicate the optical traffic upon a failure in the working path; 
 the protection path comprising two or more network elements coupled together by optical lines; and 
 while communicating optical traffic along the working path, monitoring an idle signal of the protection path to detect an error in the protection path comprising an error in a component of or more of the network elements. 
 
   
   
     20. The logic of  claim 19 , further operable when executed to perform the step of generating an alarm upon detection of an error in the protection path. 
   
   
     21. The logic of  claim 19 , wherein:
 each of the two or more network elements comprises a switch fabric unit along the protection path;
 the protection path comprises one or more spans interconnecting switch fabric units of adjacent network elements of the two or more network elements; 
 the one or more spans comprising:
 an optical line between the adjacent network elements; 
 interface units between the interconnected switch fabric units; 
 backplanes coupling together components between the interconnected switch fabric units within the adjacent network elements; and 
 the switch fabric units of the adjacent network elements; and 
 
 the logic operable when executed to perform the step of monitoring an idle signal of the protection path to detect an error in the protection path comprises the logic operable when executed to perform the step of monitoring each of the one or more spans of the protection path. 
 
 
   
   
     22. The logic of  claim 19 , wherein the step of monitoring an idle signal of the protection path to detect an error in the protection path comprising an error in a component of one or more of the network elements comprises the step of monitoring an idle signal of the protection path to detect an error in the protection path comprising an error in a backplane of one or more of the network elements. 
   
   
     23. The logic of  claim 19 , wherein the step of monitoring an idle signal of the protection path to detect an error in the protection path comprising an error in a component of one or more of the network elements comprises the step of monitoring an idle signal of the protection path to detect an error in the protection path comprising an error in an interface unit of one or more of the network elements. 
   
   
     24. The logic of  claim 19 , wherein the step of monitoring an idle signal of the protection path to detect an error in the protection path comprising an error in a component of one or more of the network elements comprises the step of monitoring an idle signal of the protection path to detect an error in the protection path comprising an error in a switch fabric unit of one or more of the network elements. 
   
   
     25. The logic of  claim 19 , wherein the step of monitoring an idle signal to detect an error comprises the step of monitoring a B3 byte of the idle signal to detect a bit error rate error. 
   
   
     26. The logic of  claim 19 , wherein the step of monitoring an idle signal to detect an error comprises the step of monitoring H1 and H2 bytes of the idle signal to detect a loss of pointer-path error. 
   
   
     27. The logic of  claim 19 , wherein the step of monitoring an idle signal to detect an error comprises the step of monitoring H1 and H2 bytes of the idle signal to detect an alarm indication signal-path error. 
   
   
     28. A method for monitoring an optical network, comprising:
 communicating optical traffic along a working path of an optical network; 
 the optical network comprising a protection path for the optical traffic to communicate the optical traffic upon a failure in the working path; 
 the protection path comprising two or more network elements coupled together by optical lines; 
 while communicating optical traffic along the working path, monitoring an idle signal of the protection path to detect an error in the protection path comprising an error in a backplane, an interface unit or a switch fabric unit of one or more of the network elements; 
 generating an alarm upon detection of an error in the protection path; and 
 the error comprising one or more of a bit error rate error, a loss of pointer-path error or an alarm indication signal-path error. 
 
   
   
     29. The method of  claim 28 , wherein:
 each of the two or more network elements comprises a switch fabric unit along the protection path; 
 the protection path comprises one or more spans interconnecting switch fabric units of adjacent network elements of the two or more network elements; 
 the one or more spans comprising:
 an optical line between the adjacent network elements; 
 interface units between the interconnected switch fabric units; 
 backplanes coupling together components between the interconnected switch fabric units within the adjacent network elements; and 
 the switch fabric units of the adjacent network elements; and 
 
 monitoring an idle signal of the protection path to detect an error in the protection path comprises monitoring each of the one or more spans of the protection path.